Database Erd Generator Application help

[smokyyyyyy]

My first language is not english so bear with my english.

I want to make erd generatoor in PHP

in this application user enter table name and its attriubutes and when user click on generate button it will make erd and also make releations between tables.System should make relations itself

i have completed one phaze give table name and attibutes and click on generate erd button it draw table .Can any one tell me how to make relations functionality?

if you know any tutorial similar to this site will be much appreciated .

or just tell me the logic or instruction how to implement.

Regards